Mixing apparatus



Jan. 13, 1942. G: DU RlETz ET AL MIXING APPARATUS Filed Oct. 3l, 1959 2 Sheets-Sheet l i im BY ZZ Patented Jan. 13, 1942 MIXING APPARATUS Gsta Du Riet: and Lars Johan Faith Ell, Stockbolm. Sweden, assignors to Aktiebolaget Elektrolux, Stockholm, Sweden, a corporation of Sweden Application October 31, 1939, Serial No. 302,126 In Sweden November 1, 1938 4 Claims.

This invention relates to machines for kneading, crushing, mixing, churning, beating, whipping and similar operations, consisting oi a rotatable container and one or several rollers or the like, resting directly or indirectly against thef inner side of this container and which are t rotate around their own axes essentially parallel to the turning axis of the container when the line V-V of Fig. l;

Fig. 6 is a cross-sectional view taken on the line VI-VI of Fig. 1;

Fig. 'I is a view, partially in cross-section, illustrating a portion 'of the container shown in Fig. 1;

Fig. 8 is a cross-sectional view taken on the line V'III-VIII-of Fig. 1:

Fig. 9 is a view of a motor support;

Fig. 10 is a cross-sectional view taken on the line X-X of Fig. 9:

Fig. 11 is a top view of a portion of the device shown in Fig. 1; and

Fig. 12 is a view, partially in cross-section,

the housing 20, the upper end of which is provided with a connecting member consisting, in the embodiment shown, of a non-circular (preferably rectangular) pin 22 and a sleeve 80 which surrounds the pin and is attached to the end of the shaft. The container of the apparatus, in other words the receptacle for receiving the ingredients to be acted upon, is designated by 23. Its bottom 24 is flat in the embodiment shown and is provided, on its lower side, with an inverted cup-shaped member 25, preferably arranged in the center. This member surrounds a coupling member 26, rmly connected, directly or indirectly, with the bottom 24. The lower end of this member is formed with a groove 21 intended to cooperate with the pin 22 when the member 28 is received within the sleeve 80. Sleeve 80 and member 26 may be conical in order to provide a tighter t. The member 25 may possibly be developed as a handle for the container or serve as a connecting member for the same. The height of the coupling member 26 is equal to or less than that of member 2l, as a result of which container 23, after having been removed from the apparatus, may be placed on a flat surface, for instance a table or the like, without'any danger oi' its turning over. In order to increase the stability of the container under these conditions, the member 25 is given a comparatively large diameter.

A tubular pillar 28 is rmly connected with stand I0, and preferably extends parallel to the showing the location, of a switch and electrical connections.

In the drawings, I0 designates the apparatus stand, consisting essentially of a number 'of housings or casings enclosing the various driving and over a pulley I8 mounted on the shaft I1 u which carries the worm I4. The belt transmission consisting of parts I3, l5 and I8, is covered by a housing I3, while the worm I4 and the worm gear I5 are placed in a housing 20; The worm axis o1' the container 23 and directly outside of the container wall. In order to prevent objects .from being wedged between the pillar 28 and the container 23, a protective plate 29 or a bolt 30 may be provided, as shown in Fig. 11. From the Yupper end of the pillar 28 there extends an arm 3l supported thereby in a turnable manner. Ro'- vtatably supported Vat the end of this armby means of a spindle 33 is an agitator member 32.

In order to be easily removed from or inserted into the agitator, spindle 33 .is provided with an easily accessible button 34. The upper end of agitator 32 isrmly connected with a. roller 35, made of rubber or` any other suitable material, and arranged to bear against the inturned upper edge 36 of the container 23 under certain circumstances. For this purpose the roller 35 is provided with a peripheral groove 31. Arm 3i forms at its extreme end a. handle 38, by means of which the arm and consequently also the agitator 32, may be brought toward and beyond the center gear is rmly attached to a shaft 2|, supported in 55 of the container 23. l The opposite end of the arm Il is formed with a peg Il which is inserted in the upper end of the tubular pillar 25 and can turn in same (Fig. A spring 4I is connected between the lower end of peg 39 and a part 40 secured to the lower end of pillar 23. This spring is arranged in such a manner that it always tends to turn the peg I9, and consequently arm 3|. in the same direction, in the embodiment shown, counter-clockwise. Spring 4I consequently acts as a torsion spring. Around the upper end of the pillar 28 a sleeve 42, provided with a preferably axial split 48, is arranged. This sleeve is provided with a groove 43, extending about onequarter of the periphery oi' the sleeve. A corresponding groove is arranged in the tubular pillar 28. A pin 44, threaded at its outer end, and firmly attached to peg 39, projects through these grooves. The swinging motion of the arm 3i is thus limited by groove 43, against the outer walls of which pin 44 will rest in its end positions. Arm 3| may be locked in any desired position by a wing nut 45, which is screwed on the outer end of the pin 44 against `a preferably spiral cam 46, arranged on sleeve 42. This cam forms an oblique resting surface for nut 45, for which reason the motion oi the arm is locked in only one direction. namely in the direction toward the lateral wall of the container. As a matter of fact, it is extremely important that agitator 32 can move freely towards the center of the container in case solid particles of the mass should pass between the agitator and the container Walls. Sleeve 42 is attached to the pillar 29 by means of one or several screws 41 which cause the sleeve to be clamped to the pillar 28. Sleeve 42 supports an arm 49, the outer end of which extends into container 23 and carries a scraper 5t. 'I'he purpose of this scraper is to remove the contents oi' the container from its walls. The arm 49 is guided by a groove 5I provided in a bridge 52 extending from the sleevel 42. The part 53 oi' the arm 49 extends at approximately right angles to the principal part of the arm and is supported in a displaceable manner in an opening of projection 54 of the sleeve 42. Arm 49 can be raised and lowered by the action oi a screw 55 attached to the lower part of the projection 54 (Fig. 3). This screw may be locked by means of a locking nut 55. Due to such an adjusting possibility, deviations occurring during the manufacture, can be compensated as well as deviations resulting from the wear of the scraper. Scraper 50 may preferably be composed of wood, Bakelite or some other suitable material. The distance between scraper 50 and the container wall may be varied by unfastening sleeve 42 by slightly,1 loosening screws 41. Arm 49 may be removed from the apparatus together with the scraper by pulling the arm member 43 through the opening in the projection 54.

On bridge 52 an appendage 51 is arranged, serving as a support for the apparatus when set on its side for instance when, instead of container 23, a meat grinder, coffee grinder, or a similar household apparatus is to be connected to the worm gear shaft 2|. In addition to the appendage 51, the apparatus rests in that case on two appendages 58 arranged on the housing I9. Appendages 51 and 58 are preferably made of rubber or similar material. The appendages may be in the form of suction cups.

In this position of the apparatus the container 23 has been removed. In the other' position of the apparatus, namelyas shown in Fig. 1, it rests on four legs 15, 11, 13, also preferably made of rubber. Two of the legs 15 may be arranged on the lower side of the motor housing I2, the leg 11 on the lower side of the housing I9 surrounding the belt transmission, and leg 18 on the lower side of the worm gear housing 2U. In order to impart to the apparatus the greatest possible stability, the stand I 0 is preferably made of heavy material as, for instance, cast iron or the like. The distances between the appendages 51 and 5I, and legs 16, 11 and 18, are, however, comparatively large, assuring adequate stability even if a lighter material as, for instance, aluminum or Bakelite is used. Especially the distances between appendages 51 and 58 have been made large by placing appendage 51 at a great distance from the appendages connected with the stand proper. This is necessary in order to connect a meat chopper or some other comparatively heavy additional device to the worm gear shaft 2i without running the risk of the apparatus overturning. The connection of the rotating part oi the additional device is effected in the same manner as the connection oir container 23, while the stationary part of the device may be connected in such a manner, for instance, that a sleeve or the like connected with the device, is placed on and screwed to a stationary support Bl surrounding the sleeve and connected with the worm gear housing 2D. In the upper part of the intermediate space between the sleeve B0 and the support 8l a tightening ring 82 of felt or the like is inserted, which is pressed by a spring 83 against a flange protruding from the uppermost part of the sleeve 80. The felt ring serves as a tightening member for the Worm gear and its support and prevents splashing water and the like from penetrating into it.

The carbon brushes of the motor I I are preferably disposed at the intersection of planes parallel to the plane of legs 16, 11 and 18 and to the plane of appendages 51 and 58, respectively, whereby the brushes are horizontal in either position of the apparatus.

The driving motor I I is provided with a ventilating fan 59 intended to draw cold air through the channel B0 into'the motor housing I2 and through openings 6I irito the cap oi? a bearing of the motor. The air flows through corresponding openings 62 into the other bearing cap and further through openings 63 (Fig. il) into the housing surrounding the belt transmission. This air is discharged through opening 64 in the housing I9. By means of this air current not only the driving motor but also the belt is cooled, in addition to which the air also passes the inner wall of the worm gear housing 2U.

The pulley I8 is so dimensioned with respect to the pulley I6 `that the Worm it, connected with the pulley, will rotate at a speed corresponding to a value ranging between one-half and one-nfth of the speed of the motor. Thus the principal reduction of the speed in the motor takes place in the Worm gear. Its housing 20 is preferably illled with oil or grease. The worm I4, as appears from the drawingfis supported on one side only by means of two bearings, 65 and 51, due to which the worm I4 and both these bearings, with the bearing seat 68, form a demountable unit.

All ventilation openings in the housing and casings of the stand are developed in the form oi slits, arranged on the lower side of the stand, so that splashing water or the like cannot penetrate into the driving members of the apparatus. The

space in which the belt transmission is arranged is divided by a partition 1h in to a separate chamber 1I in which the electric switch 12 and the plug receptacle 13 are arranged. The driving motor II is connected with its housing I2 contained in the stand I in such a manner that a special protecting insulation is provided between the parts II and I2. This insulation consists of a sleeve 14 anda ring 15 preferably made of rubber or similar elastic, and electrically-insulating, material. The rubber sleeve 14 is developed as a funnel and intended to convey the cooling air for the driving members. The pulling strain on the pulley I6 caused by the belt I3 is received by the rubber sleeve 14. Due to the fact that the driving motor II is thus elastically connected with the stand'of the apparatus, vibrations from the motor are prevented as far as possible from being transmitted to the stand. Due to the fact that belt I3 is preferably made oi' rubber, the pulley I8 is also electrically insulated from the motor. Insulation may also be provided by making the pulley I8 of dielectric material, for instance, Bakelite.

As machines of this kind are subjected to very diirerent loads, for instance, when they are combined with a meat grinder, it is` advisable to'arrange a'n overload protection for the motor. This consists in the present case, for instance, therein that the belt is dirnensioned in such a manner that in case of a heavy load ittends to slide oiI the pulley I6. In order to enable the belt to slide off the pulley I6 when the driving members are loaded too heavily, the space 69 has been widened externally. Other overload protecting devices as, for instance, sliding connections and the like, are, of course, also possible.

The scraper arranged in the container may be provided on the side opposite 'the inside of the container, with a recess which is preferably located in the front part of the scraper, namely, the part facing the moving direction of the conbeing rotatably supported by said arm and another portion extending into said container, and a scraper carried by the latter portion for contactin'g the interior of said container.

2. In an apparatus of the class described, a frame including a base and an arm extending substantially at right angles thereto, a container rotatably mounted on said base, means for rotating said container, an agitator within said container, means for rotatably supporting said agitator from said arm, a member having parallel 'vertical legs connected by a horizontal portion,

one of said legs being rotatably and removably supported by said arm and the other leg extending into said container, and a scraper carried by I said other leg for contacting the interior of said container, said arm being formed with a horizontal groove for receiving the horizontal portion of said member for preventing rotation thereof.

3. In an apparatus of the class described, a frame including a base and an arm extending substantially at right angles thereto, a container rotatably mounted on said base. means for rotating said container, an agitator within said container, a member swingably mounted on said arm for swingably and rotatably supporting said agitator within said container, means carried by said arm for limiting the swinging movement of said agitator towards the side wall of said container, a member having substantially parallel portions, one o! said'portions being rotatably supported by said ,arm and another portion extendtainer. Under certain circumstances the scraper l stantially parallel portions, one of said portions ing into said container, and a scraper carried by the latter portion for contacting the interior of said container.

4. In an apparatus of the class` described, a frame including a base and an arm extending substantially at right angles thereto, a container rotatably mounted on said base, means for rotating said container, an agitator within saidv container, a member swingably mounted on said arm for swingably and rotatably supporting said agitator within said container, a spiral cam on said arm, an adjustable stop element carried by said member and cooperating with said cam to `adjustably limit the swinging movement of said agitator towards the side wall of said container, a member having substantially parallel portions, one of said portions being rotatably supported by said arm and another portion extending into said container, and a scraper carried by the latter portion for contacting the interior of said container.

, Gs'ra DU Rmrz.

LARSJOHAN FAITH ELL. 

